According to known methods the articulation of the hip is replaced by two prostheses, to with, a prosthesis of the neck of the femur and a prosthesis of the acetabulum of the hip-bone. One of the methods used for positioning such prostheses is the trochanterotomy which consists in cutting the trochanter major to which the ligaments of the mean gluteal muscles (gluteus medius) are attached, whereby the medullary canal or duct becomes more easily accessible, the tail portion of the femur neck prosthesis being then introduced into said duct and cemented therein. The trochanter major is then reintroduced onto the femur and fixed in this position by various means the nature of which depends on the surgeons carrying out the operation.
Amongst said various means, reference may be made, in the first place, to a one-ply wire used to surround the trochanter major so to press it against the femur. Such an attachment means is difficult to use since it fails to conform easily to the bone; also, it requires a fixation obtained by twisting and, furthermore, it irritates the muscular masses.
Other surgeons use screwed-on plates, hooks and clamps either separately or in combination with metallic encircling components; however these attachments are bulky and difficult to position in the desired site. In fact these metallic elements are too rigid to be suitable for use unless they are specially adapted to the conditions of each particular case. Furthermore their implantation at the level of the gluteus medius tendon is difficult and uncertain on account of the muscular contractions.
The one-ply wire used in most cases can be replaced by a multi-ply cable which exhibits greater flexibility and mechanical resistance and is easier to handle than the one-ply (or single-strand) wire, but is more difficult to fix since it requires the use of a plate disposed at the level of the gluteus medius tendon.
In addition to the above outlined drawbacks all the known means mentioned herein-before are unsatisfactory in that they fail to exhibit, on account of their position, a required maximum strength with respect to the tractive forces of the muscles attached to the trochanter major, since they are meant essentially to apply the trochanter major against the longitudinal portion of the femur while maintaining a transverse pressure, whereas the tractive forces of the muscles are exerted mainly in the longitudinal direction.
It is one object of the present invention to provide an attaching device, especially for attaching the trochanter major to the femur, which confers on the trochanter major a greater resistance to the tractive forces of the muscles that are attached thereto.
It is also an object of the present invention to provide an attaching device comprising multi-ply cable means and simple multi-ply cable fixing means which are not undesirably bulky.
It is a further object of the invention to provide tools for positioning the attaching device according to the invention in a desired site.